What is the truth and how may I know it?

https://www.lds.org/broadcasts/article/ces-devotionals/2013/01/what-is-truth?lang=eng

"How can we find truth?
I believe that our Father in Heaven is pleased with His children when they use their talents and mental faculties to earnestly discover truth. Over the centuries many wise men and women—through logic, reason, scientific inquiry, and, yes, through inspiration—have discovered truth. These discoveries have enriched mankind, improved our lives, and inspired joy, wonder, and awe.
Even so, the things we once thought we knew are continually being enhanced, modified, or even contradicted by enterprising scholars who seek to understand truth."

https://www.lds.org/manual/teachings-of-presidents-of-the-church-joseph-fielding-smith/chapter-10-our-search-for-truth?lang=eng

"If we will hearken unto the words of the Lord and search for ourselves and obtain knowledge from the Book of Mormon, from the Bible, from the Doctrine and Covenants, from the Pearl of Great Price, and from the instruction given us from time to time by the authorities of the Church, and seek to do the will of the Lord, remembering our prayers and our covenants before him, we will not go astray.
In the ninth Article of Faith we declare that “We believe all that God has revealed, all that He does now reveal, and we believe that He will yet reveal many great and important things pertaining to the Kingdom of God.” This being true, it becomes necessary for us to understand all that He has revealed, and that which He is now revealing; otherwise we are not in touch with His work and cannot know His will concerning us, for we do not comprehend it."

https://www.lds.org/topics/gospel-study?lang=eng

"As we patiently and diligently seek learning by study and also by faith, we will “grow in the knowledge of the glory of him that created [us], or in the knowledge of that which is just and true” (Mosiah 4:12), for He promises, “Draw near unto me and I will draw near unto you; seek me diligently and ye shall find me; ask, and ye shall receive; knock, and it shall be opened unto you” (D&C 88:63)."

I shall conclude with ths same verse from the New Testament that Joseph Smith Jr. read that lead him to ask God which church was true:

"If you need wisdom, ask our generous God, and he will give it to you. He will not rebuke you for asking." James1:5 NLT